Pepperl+Fuchs HID2891 Manual page 35

Frequency Converter HiD2891
Examples
− The speed of an agitator will be indicated in rpm (or rps). The agitator consists of 8 stirring
blades that are recorded by the sensor. You should therefore enter 8 pulses per unit
(revolution).
− The flow rate recorded by a water meter will be indicated in l/min (or l/h). The meter returns 20
pulses per liter. Enter this value. For a display in m³/h, enter 20,000 pulses per unit (m³).
− The speed of a conveyor belt will be entered in m/s (or km/h). The sensor records 8 pulses per
revolution on the drive wheel. The drive wheel has a diameter of 0.4 m and thus a circumference
of 1.256 m. You should therefore enter 8 x 1000 / 1.256 = 6369 pulses per unit (m).
• Detect Lead Breakage:
Lead breakage monitoring tests whether there is no current flowing for terminal 3 (LB = lead
breakage).
A suitable parallel resistor must be present in the sensor or externally for lead breakage monitoring
(see page 11).
Lead breakage monitoring is not possible for NPN sensors and push-pull power amplifiers. If a
sensor of this type is used, LB must always be deactivated with  Active
• Detect Short Circuit:
Short circuit monitoring tests whether the input current is too high for terminal 3 (SC = short circuit).
A suitable series resistor must be present in the sensor or externally for short circuit monitoring (see
page 11).
• Debounce Filter:
A bounce filter is required when a mechanical contact is used. You can use the bounce filter if the
frequencies that will be processed are always below 10 Hz.

Activating and deactivating line monitoring and debounce filter.
 Activate the monitoring system with  Active.

Deactivate the monitoring system with  Active.
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